1. Field of the Invention
The present invention relates to a piezoelectric pump for a household electric appliance and more particularly relates to a piezoelectric pump comprising a moving wall interposed between a first casing element, defining a pumping chamber with the moving wall, and a second casing element applying pressure to the periphery of the moving wall in order to hold the latter in position.
2. Description of Related Art
Japanese patent application #62142597 discloses a clothing iron comprising a piezoelectric pump that supplies a vaporization chamber with water from a receptacle. This document describes a piezoelectric pump comprising a moving wall interposed between a first element, defining a pumping chamber with the moving wall, and a second element applying pressure to the periphery of the mobile wall in order to hold the latter in position.
In a customary fashion, the first and second casing elements are fastened together by gluing, screwing, or ultrasound welding. Such assembly means, however, have the disadvantage of allowing a certain degree of relaxation of the pump elements over time, particular under the effect of temperature fluctuations. This phenomenon is accentuated when the elements of the piezoelectric pump are made of plastic.
The performance of a piezoelectric pump is closely linked to the dimensions of the pumping chamber. Hence the phenomenon of relaxation of the means for assembling the various parts of the casing can lead to a significant decline in pump performance. These same factors make it equally difficult to mass produce piezoelectric pumps with uniform performance characteristics.